Water-Cooling an OS 4-Stroke

[A-37]

I recall that OS used to make a .61 4-Stroke marine engine. Has anyone had success water-cooling a 4-stroke with a fabricated jacket? I'd like to convert my .91 Surpass but need some ideas from the experts out there. Haven't had any luck with soft copper tubing. Tried flattening it a bit but that won't work either.

[Doubledog]

What about aluminum tube? Thats one of the things they use to cool electro's down to the 05 size motors. Easy to work with. I think its 2-3mm ID.

Whats your project?

[A-37]

One of the problems is winding the tubing between the cylinder fins and the pushrod tubes. Also, the fuel intake pipe gets in the way. It's much more difficult than winding tubing around a 2-stroke.

The boat is a 45" DV which has a G23. I'm tired of all the noise and would prefer to power the boat with my OS .91 4-stroke. I don't race. It's just a sport boat.


Thanks for your tubing tip.

BTW, I wrote to OS and suggested coming out with some large 4-stroke marine engines. Either that or offer marine conversion kits. I really think there's a market.

[Doubledog]

Have you considered other means of quieting down the G23 ? You can get it down to a whisper. My first thoughts are to install a Cooper Quiet Pipe with one of Mike T's stinger mufflers and water inject it.

[A-37]

Thanks. l I'll look into it.